As the grand disco (called ‘Xanadu’ of course) is built, romance ensues between the Muse and the Artist, even though the only thing Kira divulges about herself is that she lives with her sisters “on the second floor”.

Alas, creatures of the heavens can’t love mere mortals, and Kira is transported back up to her depressing heaven home (where there is no roller skating and no Electric Light Orchestra) and her angry father Zeus.

But Sonny bravely goes after her, roller-skating at high speed straight into a brick wall with a painting of Livy on it. Of course, it’s not a brick wall but a portal to the gaff of the gods.

Thus Wilfrid Hyde-Zeus mocks Sonny in the way only an omnipotent one can and then Olivia has a bit of a sing about needing a miracle and being suspended in time, and pleads that she be allowed to come back for just one night.

Sure enough, Kira is back to grace Xanadu’s opening night. To Sonny’s beguilement, she dances and sings in one of the wildest multiple-personality dance/skate floor shows the 70s have ever seen.

And then the fun continues with a bizarre battle of the bands in which a swanky Glenn Miller-type big band goes up against metal rock group The Tubes. It’s sheer cacophony at first, but then the disparate sounds begin to merge into one big eclectic crescendo – and if you thought there was no thematic substance in this roller skate romp, shame on you.

Xanadu had its origins firmly in the Hollywood musicals of the 1940’s (in fact Gene Kelly’s character was called Danny McGuire – the same name he had in Columbia’s Cover Girl in 1944).

Robert Greenwald directed from a screenplay by Richard Christian Danus, Michael Kane and Marc Reid Rubel, and the musical numbers were staged (very well) by Kenny Ortega and Jerry Trent.

The movie contained some splendid songs, primarily from ELO, with some lovely ballads such as Magic (by Olivia Newton-John) and Suddenly (featuring Newton-John in a gorgeous duet with Cliff Richard).